Investigations into the biochemical mechanisms of pulmonary emphysema: effects of cigarette smoke on enzymes and anti-enzymes in the lung.

The mechanism(s) causing emphysema in the cigarette smoker are still poorly understood. However, circumstantial evidence is beginning to provide a tenuous link between smoking and the protease-antiprotease imbalance hypothesis. Independent effects on elastin synthesis may also be important. This triad of chemical and cellular events (leukocyte recruitment, inhibitor inactivation, depressed tissue repair) constitutes a reasonable first approximation from which to approach this complex question.